use.c

来自「一个用C编写的简单的关系数据库系统」· C语言 代码 · 共 55 行

int Use(DBF * dbf_name, char * commond)
{
	char use_name[TABLE_NAME_LENGTH];
	int use = -1;
	int i = 0;

	commond = strtok(commond," ");
	commond = strtok(NULL," ");

	if (commond == NULL)
	{
		puts("	命令格式错误，请输入要打开的关系名/n");
		return ERROR;
	}
	if (strlen(commond) > TABLE_NAME_LENGTH)
	{
		puts("	输入表名错误");
		return ERROR;
	}
	strcpy(use_name,commond);
	commond = strtok(NULL," ");
	if (commond != NULL)
	{
		printf("	命令格式错误，多于字符串 %s/n", commond);
		return use;
	}
	for (i=0; i<MAX_OPENED_COUNT; i++)
	{
		if (strcmpi(use_name, dbf_name[i].dhName) == 0)
		{
			use = i;
			break;
		}
	}

	if (use != -1)
	{
		printf("\n	记录格式:");
		for (i=0; i<dbf_name[use].dhFieldCount; i++)
		{
			switch (dbf_name[use].dbf_struct[i].dhFieldType) {
			case Int:
				printf("	%s(int)   ",dbf_name[use].dbf_struct[i].dhFieldName);
				break;
			case Float:
				printf("	%s(float)   ",dbf_name[use].dbf_struct[i].dhFieldName);
				break;
			default :
				printf("	%s(string %d)   ",dbf_name[use].dbf_struct[i].dhFieldName,dbf_name[use].dbf_struct[i].dhFieldLen);
				break;
			}
		}
	}
	return use;
}